Sighn, resign, foreign Silent 'g'
Knock, know, knee Silent 'k'
Listen, mortgage, watch Silent 't'
Hour, ghost, honest Silent 'h'
Autumn, damn, column. Silent 'n'
Thumb, doubt, plumber Silent 'b'
Wrist, wrote, wrong Silent 'w'
Half, calm, talk Silent 'l'
Guess, guard, tongue Silent 'u'